Boring tool



April 9, 1940- c. KlTLi-:Y 2,196,311

BORING TOOL Filed Nov. 14, 1958 INVENTOK, C2 V05 /f/nfy am TTORNEY Patented Apr. 9, 1940 [UNITED STATE BORING TooL.

Clyde, Kitley, Bakersfield. Calif., y n ApplicationV November v14, 193s; serial .No. 240,241

- 4 claims. (o1. .25eelli This invention relates toa tool forv boringA holesin brittle and# similar materials such" asl brick, cement, stone and the-like. The invention has yparticular referencel tof' a-l rotary'type -of drill which-^is--adaptedto beplaced inl an augerv 0r brace which, may bel hand operated or-machine operated; Thedrill has 4oneend` designedK to lit and nbe held Jin Ythe' chuckjof an auger orf-'brace and thel like, and another-'end coniiguratedl andVl shaped-to rapidlywzuty its way through'the ma `v terial when rotated: Itis providedy with cuttingr and chipping/'edges and points and of" a spreadsuitable toprovideethe-particular size hole desired.` The cutting' andy clipping edges and points are alined ina -man-nerto eiciently cooperate to borer a clean andI neat hole with a minimum: of energy'.

A- pluralityfof cutting and/or:- chipping ledges. are providedjand shapedso as;notfto,;grindits Way through .the ,material beingboredbut rather to chip its way in a self feeding action. Av bevy elled .cutting edge -isI taken advantage-of, however,

for keeping the hole clean asthechipping edges.r

and/or. pointsprick andA make their waythrough the.. material. and-.t0- cause,l the continuation ofthe pricking action of the cutting edges, the tool'is divided into a. plurality of elongated and-substantially parallel armsforprongs which are'tempered'and shaped'ztcr-provide"an elasticaction. vThis elasti'cz-action-l-andcthe general'operationof the tool" will be=-better'understood :when thenspecifications .are readwiriV connection with.. the accompanying drawingr.. f

An object of eral and cementitious materials and the like.

Another object of this invention is to provide a boring tool having elastic properties for causing its cutting edges and points to prick and chip their Way through the material being bored.

Another object is to provide a drill which is rotary in action and set to provide a clean hole in a minimum of time and power.

A still further object is the provision of a boring instrument having an elastic and vibratory rotary action capable of maintaining its cutting edges for a long period of time.

Other objects, advantages and features of my invention will appear from the accompanying drawing, the subjoined detailed description, the preamble of this specification and the appended claims.

Applicant is about to illustrate and describe one 'of the forms of his invention in order to teach one how to make, use and vend the same,

In.order tov effectively promote.

this invention is to expose means;v andmethodsfon-:boring a hole'in siliceous, minnear theiry cutting ends.

but f it is-A to be understood that the'Y drawing and descriptiolrthereof'are notto limit thelinvention/ in any sensewhatsoever, except aslimited bysthe*I vappended' claims. -f

Inf-they drawing: f Y y y Figj-l 'ofthe drawingl shows the invention-in plan view.

Fig.; 2 `shows af* side viewv thereof'.

Figs f'shiows an endview of thecutting endy of the drill.

Fig.` 4 shows'a section taken substantially along' the line 4-4'of'Fig; 2. v

Thepreferredf form of the-invention shows the drill asl having a shank-I Whichy maybe roundI in" cro/ssJ section -o'r lofl somel other suitable configuration,` and' which is integral with a tapered head Zdesigned to-iit thesocket or chuck of an augerr andthe like, not shown.A Integral withv theA shank-is a split-'drill end 3 which is prefere` ably conguratedras"shown;` These elements areA preferably made` of Va--high grade tool steel having the necessary strength and elasticity `for'the purposes intended; Thev grade and kind of materia-l used for; making' the' boring instrument or drill' will'ldepend `largely upon the kind and ltypeof material toxbe'bored. Thehead of the' drill may'be'threadedor-otherwise treated Where it lof is'to ybe attachedeto'lon'gstems,ltubes and the like-l' when Yused'fforI well.' drilling.v and test drillinglin" mining.

The drill end.3tcomprisesitwoarms @or .prongs 4 a-nd-.5-which areformed r .witlirabbfetsI inthegman.- nershownsmostzclearly inwli'gs. 3`.and4, consist'-j ingoflthelaps and: 5.' These rabbeted' arms run injuxtaposedrparallelismalong.- the.. major; part of the lengths of the arms and extend to The cutting ends are swaged to form bent or curved portions 6 and 'l so as to form a gap 8 having divergent curved walls including the laps ll' and 5. 'Ihe extreme ends of the arms li and 5 are ground to form the bevelled surfaces 9 and lil respectively to produce sharp keen edges Il and i2 respectively. The grinding produces the pricking or chipping points i3 land I4 which are the leading cutters for the drill as it progresses through the material are automatically i'ed from the hole due to the 55 upward pressure of the newly formed chips at the bottom of the hole.

The edges II and I2 are preferably ground so as to cause one of the points I3 and I4 to slightly protrude beyond the other so they will materially aid in starting the drill in hard substances.

The edges on either side of the points I3 and I 4 are slightly biased, as shown, so as to make the chippers I3 and I4 more effective in their action. As the chippers I3 and I4 dig into the material to be removed, their respective prongs will undergo a bending stress and spring slightly backward until points overcome the sheer stress of the material being cut, in which event points will spring forward and quickly chip away a small bit of the material. This action will continuously repeat itself with both points and cause a constant vibration of them and the arms 4 and 5. By continuously turning the drill, the chippers I3 and I4 will alternately dig and chip as pressure is applied to the drill during the rotary action. In order to prevent binding of the drill as the following Aupper sections of the arms 4 and 5 enter the hole as the chippers progress, the arms are tapered or biased along their outer edges I5 and I6 so that the widest part is at the cutting ends.

The rabbeted split along the body of the drill 3 performs a very important function and is indispensable toward making the instrument an effective driller. The split divides the drill into two halves having the overlapping parts v4' and 5 which support and brace one another while the arms 4 and 5 are under bending stresses. The rabbeted split prevents the halves from slipping past one another and then twisting around one another. The rabbet portion of the split also prevents the halves from crowding and thus wedging the drill in the hole. Because of the rabbets, the drill arms have a true reiiexive action as their chipper points vibrate during the boring performance.

. The bit of the tool is made long so as to allow plenty of material for resharping and dressing it. The bit can be swaged cold on the job where it is used and the chipper points spread to make the desired size hole. The sides of the bit may be led so as to reduce its spread when it is required to make a hole having some particular diameter so as to fit a certain sized peg or plug.

In practice, it has been found that the bit is more effective in drilling very hard substances when the chipping points are spread far apart, whereas softer materials can be drilled better when the points are not spread very much. In

either event, the side walls of the hole are cut clean and smooth so that no small particles will remain attached to the walls and tend to lubricate the movement of pegs and plugs wedged therein. It has been found that when small particles remain in the hole, inserted pegs do not become as tightly seated as when the walls of the hole are clean.

Having thus described and illustrated a preferred form of the invention, I claim the followmg:

1. A boring tool including a pair of strips xed together at one of their ends and having their other ends free, said free ends being sprung apart in one direction and swaged apart in another direction, ground surfaces at said free ends forming cutting edges which converge toward one another forming chipping points substantially along an axial plane of the tool, the strips being provided along their adjacent sides with rabbets, and said rabbets being spaced apart at the free ends of the strips and abutting one another at their central portions.l

2. A boring tool having a plurality of strips joined together at one of their ends and free at their other ends, a rabbet along the adjacent sides of each strip abutting each other along the central portions thereof, a bias cutting edge at the free end of each strip terminating into chipping points, said free ends having a portion thereof swaged apart and outwardly from the axis of the tool and also bent apart and outwardly at right angles to the swaged position.

3. In a boring tool having a plurality of blades with upper integral ends and free lower ends, cutting means at the extreme lower ends of the blades, opposed faces of said blades having rabbets, said lower ends being sprung and swaged at right angles to provide outwardly toed chipping points.

4. In a drilling device for making holes in stone, brick, concrete and similar materials, a pair of metal strips having one of their ends joined together to form an integral shank and the other ends being free to vibrate, a rabbet along the opposing faces of the strips having Contact with one another at points removed from the free ends of the strips, a bias cutting edge at the free end of each strip terminating into chipping points, said free ends having the lower portion thereof bent apart, and also swaged apart in a direction at right angles to the bent direction.

CLYDE KITLEY. 

